In 2002, the roadway east of Mill Avenue was re-designed as a 1.5-acre public park. The wide concrete walkway around the south and west sides of City Hall includes various types of landscaping and several park benches.

In a second phase of development, Sixth Street Park was expanded 1.5 acres to the east in 2009 as part of the construction of a 400-space parking structure next to City Hall. Tempe transformed the left-behind street level parking lot into the second part of Sixth Street Park, a green oasis in the middle of busy downtown. The expansion brings more grass, plazas, trees and art to Mill Avenue. It also features a curvilinear great walk with patterned brickwork, a shade trellis which doubles as a band shell and an artistic sundial.